1) Field of the Invention
The present invention relates to a method of collecting samples and an apparatus thereof, and more particularly, to a method of precisely collecting samples, which are not polluted, at the outside of a borehole at a predetermined depth by using a multi-packer, and an apparatus thereof.
2) Background of Related Art
Generally, underground water of landfill or a mass-burial site, underground water nearby nuclear generating plant or radioactive waste disposal facility, or underground water of a site storing CO2, that is a major contributor to global warming, in the underground thereof has been variously contaminated due to leachate. In case of a CO2 underground storage site, it has been known that the underground water contains a lot of CO2 leaked from the CO2 underground storage site.
In order to grasp the reality of the dispersal of underground water pollution or CO2, after a borehole (tube well) is formed, a sample of underground water is collected at a predetermined depth such that the quality of underground water is measured.
In this case, the predetermined depth signifies the depth of 300 m or 500 m at which a sample of underground water is collected.
Thus, when samples are collected from the same borehole at each of the depths, this may signify that samples of underground water are collected at the predetermined depth.
Meanwhile, although various schemes of collecting samples of underground water have been proposed, when the sampling of underwater are repeatedly performed at a predetermined depth, a contaminant may be dispersed from the predetermined depth to the ground in the borehole, so that it may be difficult to grasp an exact water quality at the predetermined depth.
That is, while a sample collecting container is repeatedly dropped into and retrieved from a single borehole, the underground water filling the borehole is mixed up and down, so that the contaminants contained in the underground water may be dispersed up and down or the underground water may be changed in the concentrations of the contaminants such as CO2 existing at concentrations changed according to the depth of the borehole.
Therefore, a method and apparatus for precisely collecting samples which are not contaminated at an outside of a borehole by avoiding the contamination due to mixing of contaminants (including CO2) in the borehole at the predetermined depth have not been proposed yet.
As a related art of the present invention, there is Korea Unexamined Patent Publication No. 10-2008-0104893 entitled “Liquid Collecting Apparatus” (published on Dec. 3, 2008).